Question

an administrator is creating a class that will help keep track of the courses offered. she will be using the following instance variables:

• coursename (string)
• teachername (string)
• credits (int)

option 1:
private string coursename;
private string teachername;
private int credits;

option 2:
public coursename;
public teachername;
public credits;

option 3:
public string teachername;
public string credits;
public int coursename;

which of the following would be the best way to declare these instance variables

Explanation:

🆕 New Concept Discovered: Object-Oriented Encapsulation and Variable Declaration
Keeping data safe and correctly typed

Step 1: Analyze the required variables and types

The problem asks us to declare three instance variables with specific data types:

• courseName of type String
• teacherName of type String
• credits of type int

Step 2: Apply encapsulation principles

In object-oriented programming (such as Java), instance variables should almost always be declared as private to restrict direct access from outside the class. This design principle is called encapsulation (or data hiding).

• Option 1 uses the private access modifier for all three variables.
• Option 2 and Option 3 use the public access modifier, which exposes the internal data directly and is not the best practice.

Step 3: Verify syntax and data types

Let's look at the syntax of Option 1:

private String courseName;
private String teacherName;
private int credits;

• Each variable is declared as private.
• The data types match the requirements exactly (String for names, int for credits).
• The syntax is correct.

Comparing this to the other options:

• Option 2 is missing the data types entirely (e.g., public courseName; is invalid syntax in typed languages like Java).
• Option 3 assigns the wrong data types to the variables (e.g., declaring credits as a String and courseName as an int).

Therefore, Option 1 is the best and most correct way to declare these instance variables.

Answer:

Option 1